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GB 28303-2012: Food additives -- Octenyl succinate starch sodium
GB 28303-2012
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National Food Safety Standard -
Food additive - Sodium starch octenyl succinate
食品添加剂 辛烯基琥珀酸淀粉钠
ISSUED ON: APRIL 25, 2012
IMPLEMENTED ON: JUNE 25, 2012
Issued by: Ministry of Health of the People's Republic of China
Table of Contents
1 Scope ... 3
2 Technical requirements ... 3
Annex A Test methods ... 4
Annex A
Test methods
A.1 General
Unless otherwise specified, the reagents and water used in this Standard refer
to analytical reagents and grade 3 water specified in GB/T 6682. Unless
otherwise specified, the standard titration solutions used in the test, the
standard solutions, preparations and products used in the determination of
impurities are prepared according to the provisions of GB/T 601, GB/T 602 and
GB/T 603. When the solution used in the test does not indicate which solvent
is used for preparation, it refers to aqueous solution.
A.2 Identification test
A.2.1 Iodine staining
ADD 1 g of sample to 20 mL of water, to make a suspension; ADD a few drops
of iodine solution. The color is dark blue to brown red.
A.2.2 Copper reduction
WEIGH 2.5 g of sample; PLACE it in a long-necked flask; ADD 10 mL of dilute
hydrochloric acid (0.82 mol/L) and 70 mL of water; MIX evenly; REFLUX for 3
h; COOL. TAKE 0.5 mL of the cooled solution; ADD 5 mL of hot alkaline copper
tartrate test solution; it produces a large amount of red precipitate.
To prepare alkaline copper tartrate test solution, proceed as follows:
a) Solution A: TAKE 34.66 g of copper sulfate crystals (CuSO4 · 5H2O). The
crystals shall show no signs of weathering or moisture absorption. ADD
water to dissolve and dilute to 500 mL. Keep this solution in a small sealed
container;
b) Solution B: TAKE 173 g of potassium sodium tartrate crystals
(KNaC4H4O6 · 4H2O) and 50 g of sodium hydroxide (NaOH); ADD water
to dissolve and dilute to 500 mL. Keep this solution in a small alkali-
resistant container;
c) MIX the same volume of solution A and solution B to obtain alkaline copper
tartrate test solution.
A.3 Determination of sulfur dioxide residue
A - Built-in adapter;
B - Separating funnel;
C - Round-bottom flask;
D - Gas internal takeover;
E - Condenser;
F - Connecting ball;
G - Receiver.
Figure A.1 -- Diagram of sulfur dioxide test apparatus
The apparatus in Figure A.1 is used to selectively transfer sulfur dioxide from
sample to 3 % hydrogen peroxide solution in boiling aqueous hydrochloric acid
solution. The apparatus is easier to connect than conventional apparatus. Since
the height of the 3 % hydrogen peroxide solution is above the ball tip, the back
pressure in the apparatus is unavoidable, but part F can reduce the back
pressure to the lowest possible level, thereby reducing the possibility of sulfur
dioxide loss due to leakage.
NOTE: In Figure A.1, part D needs to be equipped with a hose for connection. If polyethylene
and quartz hoses are used, they shall be pre-cooked before use in this procedure.
The entire apparatus shall be connected as shown in Figure A.1. Except for the
connection between the separatory funnel and the flask, the sealing surfaces
of all other connections shall be coated with a thin layer of piston lubricant. All
connectors shall be tightly clamped to ensure tightness during the analysis. The
separatory funnel B, of which the volume shall be greater than or equal to 100
mL. It shall be equipped with a built-in adapter A equipped with hose
connections to ensure that a certain pressure is maintained above the internal
solution. (It is not recommended to use a constant pressure titration funnel,
because the condensate may contain sulfur dioxide, which will adhere to the
inner wall of the funnel or the tube wall). The round-bottom flask C, of which the
volume is 1000 mL, with three 24/40 mm conical ports. The gas internal
takeover D shall have a sufficient length to ensure that the introduced nitrogen
can reach 2.5 cm at the bottom of the flask. The condenser E, of which the
jacket length shall be 300 mm. The connecting ball F is a glass piece made
according to the requirements of Figure A.2, which is the same size as the 50
mL measuring barrel. The 3 % hydrogen peroxide solution is placed in the
receiver G, of which the inner diameter is 2.5 cm and the length is 18 cm.
A.3.1.3.2 Preparation for determination
CONNECT the apparatus according to the requirements of Figure A.1. The
flask shall be connected to a heater with adjustable power. ADD 400 mL of
distilled water to the flask. CLOSE the valve of the separatory funnel; ADD 90
mL of 4 mol/L hydrochloric acid to the funnel. INTRODUCE nitrogen at a rate
of 200 mL/min ± 10 mL/min. ACTIVATE the coolant in the condenser at the
same time. ADD 30 mL of 3 % hydrogen peroxide solution that has been
calibrated with standard solution TO receiver G. After 15 min, the apparatus
and water will be completely deoxygenated, and the apparatus can be used for
test of samples.
A.3.1.3.3 Distillation
REMOVE the separatory funnel; quantitatively ADD the ethanol solution of the
sample to the flask. WIPE the conical connection clean with laboratory paper
towels. APPLY piston lubricant to the external connection of the separatory
funnel. REINSTALL the separatory funnel. After the connection is made, the
nitrogen flow through the 3 % hydrogen peroxide solution shall be restored
immediately, and the connection shall be checked to ensure that it is sealed.
The rubber ball above the separatory funnel is equipped with a valve to ensure
that there is sufficient pressure above the hydrochloric acid solution. OPEN the
separatory funnel valve and let the hydrochloric acid solution flow into the flask.
Continue to ensure that there is sufficient pressure above the solution. If
necessary, the valve can be temporarily closed to supplement the pressure. To
prevent the loss of sulfur dioxide into the separatory funnel, the valve shall be
closed before the last few milliliters flow out of the separatory funnel.
CONNECT the power supply for heating; CONTROL the heating speed so that
the reflux liquid is 80 drops to 90 drops per minute. After 1.75 h of distillation,
the content of the 1000 mL flask is cooled at the above reflux rate. And
TRANSFER the content of the receiver G.
A.3.1.3.4 Titration
ADD 3 drops of methyl red indicator, TITRATE the above solution with standard
titration until the yellow end point, ensuring that it does not fade within 20 s.
A.3.1.4 Calculation of results
The sulfur dioxide residue is calculated as the mass fraction w1 of sulfur dioxide,
expressed in milligrams per kilogram (mg/kg), and calculated according to
formula (A.1):